Container and cover therefor

ABSTRACT

The invention is concerned with drum-type containers, particularly plastic containers having flexible covers which form a fluid-tight seal by means of a locking action which holds the cover in positive engagement with the container.

United States Patent 11 1 1111 3,830,395 Crisci Aug. 20, 1974 [54]CONTAINER AND COVER THEREFOR 2,675,040 4/1954 Raun 220 40 17511111811104 View Eugene C1154, wellsburg, i'liiifi? Z1323 $223111?"13131123311131. 350??? 3,532,244 10/1970 Yates 3,610,306 10/1971 Summers150/.5 [73] Assgnee' vi Plasms wensburg 3,677,481 7 1972 Westfall 215 44[22] Filed: 1972 Primary ExaminerWilliam l. Price 21 Appl 307,422Assistant Examiner-R0 E. Hart Attorney, Agent, or FirmBacon & Thomas[52] U5. Ql.. 21 5/32l,-2 l5/ 3 2 9 IQQ[ Q 150/.5 [57] ABSTRACT Int. T einven io is concerned drum t ype contam- [58] Fleld of Search 220/40215/40 5 ers, particularly plastic containers having flexible coverswhich form a fluid-tight seal by means of a locking [56] Raferencs Citedavci3: 1t1h;vl;::ali1:l(:s the cover in posmve engagement UNITED STATESPATENTS 2,661,862 12/1953 Howe 220 40 9 Clams 3 D'awmg Pmmsu m 3.830.895

SHEEI 10$ 2 PAIENIEDAHBZWH iaaoass SHEET 20F 2 1 CONTAINER AND COVERTHEREFOR DESCRIPTION OF THE INVENTION This invention relates todrum-like containers having flexible covers which are engaged in apositive locking manner with the containers.

Lidded tub or drum-like containers fabricated from plastic materials,such as polyethylene, polystyrene, etc., are finding increasing use inthe food and chemical industries. The size of such containers hassteadily increased with improvement in the quality of plastic materials,and in the introduction of new materials so that gallon or 50 poundcontainers are now available. The closing and sealing of such containersgenerally relies upon the greater elasticity of plastics as comparedwith metal. In small containers an interference fit between a lid andcontainer may be sufficient. In larger containers, there is usually aninternal bead on the lid which engages an external bead near the top ofthe container wall. Either the lid or the container body or both distortto allow the beads to pass into locking engagement.

The disadvantage of this means of maintaining a lid on a container isthat external and internal forces frequently cause distortion of themating members with the result that they do not form a tight seal. Ifthe distortion is extreme the lids may even come completely off. Suchforces may be due to expansion of the contents or from the weight ofother containers when they are stacked.

In the present invention a structure is provided which applies apositive constricting force to the skirt of the lid, locking the lid inengagement with the wall of the container even when subjected to forceswhich tend to distort the lid skirt and/or container, and wouldotherwise cause them to disengage.

It is therefore an object of the invention to provide a drum-typecontainer having a cover which forms a fluid-tight seal by the action ofintegrally formed closing means.

It is a further object to provide a plastic container having a positivelocking means which is quick acting and requires only small motion.

Other objects and advantages will be apparent to one skilled in the artfrom reading the following description of the invention in conjunctionwith the accompanying drawings, wherein:

FIG. 1 is an exploded perspective view showing the top of the containerand the cover in the relative positions in which the cover is applied,with a portion of the rim of each broken away.

FIG. 2 is a sectional view showing the container and cover in contact inthe initial or unlocked position.

FIG. 3 is a sectional view with the cover in the closed or lockedposition after rotation in the direction of the large arrow.

The invention comprises generally a circular container having anexternal circumferential bead at or near the top rim of the wall, and aflexible cover having a generally horizontal body of approximately thesame size as the circular opening of the container, and having acircumferentially downwardly directed wall carrying on its inner surfacea bead adapted to engage the bead on the container wall, and carrying aplurality of outwardly directed lugs for engagement with a plurality ofcam locking means carried on a circumferential flange,

or a plurality of supports, projecting from and integral with theoutside of the wall of the container.

Referring to the drawings, the circular container 10 has a generallyvertical side wall 11 having a slight taper, the top of which isthickened externally to form a rim 12. Rim 12 has a lower surface 12asloping downward from the outer extremity of the rim to the outersurface of the side wall and a grooved upper surface 12b. Spaced fromrim l2 and integral with wall 11 is an external circumferential flange13 having a generally horizontal upper surface carrying a plurality ofspaced abutments 14 of which the leading end 14a, in relation to thedirection of rotationof the cover in closing, is further from the sidewall than the trailing end 14b. The inner side of the abutments isundercut slightly to provide an overhanging lip 14c. Reinforcing gussets13a in the angle between the lower surface of flange 13 and wall 11provide rigidity to the flange. The illustrated cover 20 has ahorizontal body portion 21 with a raised rim 22 formed by an inner wall21a, an upper wall 220, and an outer vertical wall 23 which has partialinward thickening to form bead 24 having a sloping surface 24a adaptedto engage surface 12a on rim l2. Rim 22 and walls 21a and 23 togetherdefine an inverted peripheral channel portion which includes acontinuous corrugation 22a adapted to sealingly seat in the grooved edge12b of the container side wall 11 when the container is closed. On theouter surface at the lower extremity of wall 23 is a plurality ofoutwardly directed locking lugs 25 suitably spaced and shaped to engageabutments 14 in a wedging action when the cover is rotated in relationto the container in the direction indicated by the large arrow in FIG.3. Reinforcing gussets 26 are provided between locking lugs 25 and wall23. A pair of diametrically opposed locking lugs 25 is provided withprojections 25a for tightening the lid by hand pressure or engagementwith a cooperating machine part in the automated loading and sealing ofcontainers.

The operation of applying the cover to the container will now bedescribed. Lid 20 is placed on the container with rim 22 in looseengagement with the top of wall 11. In this operation locking lugs 25will be in position between abutments 14 as seen in FIG. 2. The dottedposition of wall 23 indicates the position which it has to pass throughin order for bead 24 to clear the shoulder on rim 12. The lid is thenpressed down and flexed by inward pressure on wall 23 in the directionindicated by the small curved arrow on FIG. 3, and simultaneouslyrotated in the direction of the large arrow of FIG. 3. The inwardpressure may be applied by hand although especially in the case oflarger containers, it may be desirable to use mechanical means to exertpressure at a plurality of points or over the entire circumference ofwall 23. This will achieve a positive engagement between surfaces 12aand 24a of the rim and the cover bead, respectively, and between thelower surface of rim 22 and the grooved edge 12b of wall 11, as theouter edge of lugs 25 engage the inner surface of abutments 14 in awedging action. In the final closed position, the cover is firmly heldin locking arrangement with the container in such a way as to preventdistortion of the peripheral structure of the cover and consequentbreaking of the seal even when filled containers are stacked on top ofeach other.

It will be apparent that variations from the specific structuredescribed can be used without departing from the scope of the invention.For example, individual supports may be provided for abutments 14instead of the circumferential flange. In addition the actualconfiguration of the lugs and abutments is not critical so long as theycooperate to provide a wedging and locking action.

The materials of construction are varied and include any suitableplastic materials having the necessary rigidity and flexibilitycharacteristics, of which polystyrene and polyethylene are typicalexamples. The preferred plastics are the relatively rigid ones such ashigh impact polystyrene. It is possible to practice the presentinvention by the use of a cover made from a suitable plastic material inconjunction with a container made from another material such as a metalbut it is preferred to fabricate both the cover and the container fromplastic materials.

I claim:

1. A flexible closure lid for use with a drum-type con- I tainer havinga circular opening formed by a generally vertical side wall having atits upper end an external rim and below said rim and disposed therefroma plurality of upstanding abutments supported on said side wall and inspaced relation thereto, said closure lid comprising a circular,generally horizontal, body portion and a peripheral rim portion, saidrim portion extending upward from said body portion providing an innerwall thence outwardly providing an upper wall and then downwardlyproviding an outer wall substantially parallel to and in spacedrelationship to the inner wall, the

inner surface of said outer wall being provided with a circumferentialbead adapted for engagement below said external rim, and the outersurface of said outer wall being provided adjacent its lower extremitywith means adapted for wedging engagement with said abutments.

2. A closure lid according to claim 1 in which said means adapted forwedging engagement comprises a plurality of spaced horizontal lugs.

3. A closure lid according to claim 1 in which the lower surface of saidupper wall is convex in shape.

'4. A container comprising a body portion and a cover portion thereforadapted to form a fluid tight seal between the body portion and thecover portion by rotation of the cover relative to the body while inpositive contact therewith, comprising:

a. a drum-type body portion having a circular opening formed by agenerally vertical side wall having at its upper end an external rim andbelow said rim and disposed therefrom a plurality of upstandingabutments supported on the side wall and in spaced relation thereto, and

b. a flexible cover comprising a circular, generally horizontal bodyportion and a peripheral rim portion, said rim portion extending upwardfrom said body portion providing an inner wall thence outwardlyproviding an upper wall and then down wardly providing an outer wallsubstantially parallel to and in spaced relationship to the inner wall,the inner surface of said outer wall being provided with acircumferential bead adapted for engagement below said external rim andthe outer surface of said outer wall being provided adjacent its lowerextremity with means adapted for wedging engagement with said abutments.

5. A container according to claim 4 in which said abutments extendnormally from the upper horizontal surface of a circumferential flangesupported on said side wall.

6. A container according to claim 5 in which the leading ends of theabutments in relation to the direction of rotation of the cover whenbeing applied are at a greater distance from the side wall than thetrailing ends.

7. A container according to claim 4 in which the upper end of said sidewall has a V-shaped groove and the lower surface of said upper wall ofthe rim portion of the cover has a convex shape adapted for sealingengagement with said V-shaped groove when the container is closed.

8. A container according to claim 4 in which at least one of said bodyportion and said cover is manufactured from a thermoplastic composition.

9. A container according to claim 4 in which at least one of said bodyportion and said cover is manufactured from impact polystyrene.

1. A flexible closure lid for use with a drum-type container having acircular opening formed by a generally vertical side wall having at itsupper end an external rim and below said rim and disposed therefrom aplurality of upstanding abutments supported on said side wall and inspaced relation thereto, said closure lid comprising a circular,generally horizontal, body portion and a peripheral rim portion, saidrim portion extending upward from said body portion providing an innerwall thence outwardly providing an upper wall and then downwardlyproviding an outer wall substantially parallel to and in spacedrelationship to the inner wall, the inner surface of said outer wallbeing provided with a circumferential bead adapted for engagement belowsaid external rim, and the outer surface of said outer wall beingprovided adjacent its lower extremity with means adapted for wedgingengagement with said abutments.
 2. A closure lid according to claim 1 inwhich said means adapted for wedging engagement comprises a plurality ofspaced horizontal lugs.
 3. A closure lid according to claim 1 in whichthe lower surface of said upper wall is convex in shape.
 4. A containercomprising a body portion and a cover portion therefor adapted to form afluid tight seal between the body portion and the cover portion byrotation of the cover relative to the body while in positive contacttherewith, comprising: a. a drum-type body portion having a circularopening formed by a generally vertical side wall having at its upper endan external rim and below said rim and disposed therefrom a plurality ofupstanding abutments supported on the side wall and in spaced relationthereto, and b. a flexible cover comprising a circular, generallyhorizontal body portion and a peripheral rim portion, said rim portionextending upward from said body portion providing an inner wall thenceoutwardly providing an upper wall and then downwardly providing an outerwall substantially parallel to and in spaced relationship to the innerwall, the inner surface of said outer wall being provided with acircumferential bead adapted for engagement below said external rim andthe outer surface of said outer wall being provided adjacent its lowerextremity with means adapted for wedging engagement with said abutments.5. A container according to claim 4 in which said abutments extendnormally from the upper horizontal surface of a circumferential flangesupported on said side wall.
 6. A container according to claim 5 inwhich the leading ends of the abutments in relation to the direction ofrotation of the cover when being applied are at a greater distance fromthe side wall than the trailing ends.
 7. A container according to claim4 in which the upper end of said side wall has a V-shaped groove and thelower surface of said upper wall of the rim portion of the cover has aconvex shape adapted for sealing engagement with said V-shaped groovewhen the container is closed.
 8. A container according to claim 4 inwhich at least one of said body portion and said cover is manufacturedfrom a thermoplastic composition.
 9. A container according to claim 4 inwhich at least one of said body portion and said cover is manufacturedfrom impact polystyrene.